Signs in buildings which direct people from place to place sometimes have a message both in print, to be read by sighted people, and in braille to be read by blind people. There has been a general trend toward putting braille on signs, but this trend has been greatly accelerated because of federal legislation requiring that braille be placed on architectural signs, both new and old.
There have been numerous approaches to the problem of how to construct the braille message on an architectural sign. For example, Scott Plastics has created a line of molded, individual character sets with raised dots that either adhere to the sign face directly or are placed into a track system. The product is produced only in black or white. This system is versatile in that it can be used anywhere where aesthetics are of little concern. Custom colors must be applied by spray painting on the small pieces. The mounting is bulky and must be surface applied, which also permits it to be removed by vandals. While it fulfills the function and is cost effective, in the eyes of the architectural signage industry, this product is not entirely satisfactory.
Charleston Industries has technology which uses a metal plate coated with a photo-sensitive emulsion which is stored in a protective environment until use. The manufacturer makes a film positive or negative of the image to be incorporated onto the sign face. The film is overlayed on the photo-sensitive plate and is exposed to a light source. The area blocked out by the film remains soft and is washed away after exposure. The plate is then trimmed, painted and silkscreened or brayer rolled to highlight the raised surface. The steps to produce this product are many and require semi-skilled labor. The equipment required to produce this product is extremely expensive and this constitutes a major drawback to such a system. An advantage of this last mentioned system is that it can incorporate logos and other images, along with the raised braille portion of the sign face, but the major drawback is that the plate must be adhered to a substrate. Another major problem is that people can scrape off the raised braille dots with a fingernail.
Another product used to create architectural signs is a New Hermes Engraver, which is a computer-aided system. This system also is extremely expensive and when finished, the product is similar to the finished look of the Scott Plastics System referred to above. The braille product looks like a plate adhered to the face of the sign. This and the high cost thereof are the major drawbacks to the system.
Also on the market is a product which is a metal strip-like product fed through a machine, similar to a typewriter and wherein the person types the message on a keyboard. The machine strikes the metal strip from behind, pushing a raised dot out on the other side. The strip is then trimmed and adhered to the sign face. The metal strips can be chrome, brass or they can be painted. This, too, is a product made separate from the finished product and is adhered to the sign face upon completion. Consequently, it also can be removed by vandals and the equipment to make it has a high acquisition cost.
Accordingly, there is a need for a method and apparatus for applying braille to a sign face which overcomes the aforementioned problems.